Reports from critical care settings more than a decade ago suggested poorer clinical outcomes were associated with lower nurse
staffing, but subsequent findings from studies in neonatal intensive care units (NICUs) have been more equivocal. Profit and
colleagues have now examined outcomes for a prospective cohort of 850 moderately preterm infants (gestational age of 30–346/7 weeks) in relation to registered nurses on shift in 10 NICUs.

The measure of nursing provision used was the patient–nurse ratio (PNR). This was the average number of registered nurses
(calculated over a 24 h period of shifts, including partial nurse shifts) and occupancy in terms of NICU census of midnight
the previous day.

In addition to testing some infrequent clinical outcomes for this particular patient group …